W. Sahputra, Yohandri Bow, Rima Daniar, and Agus Manggala, “Making Biodiesel From a Mixture of Castor Oil and Used Cooking Oil in Terms of Stirring Time and Speed”, JIEETech, vol. 2, no. 1, pp. 29–32, Nov. 2024, doi: 10.36257/jieetech.v2i1.9265.